Instruction manual

EXT Split Flow Compound Turbomolecular Pumps
MAINTENANCE
PAGE
25
Mar 07 25 Issue F
The EXT Split Flow Pump is very noisy
or there is excessive vibration or both.
Is the pump rotational speed the same
as the resonant frequency of the
attached system?
If so, change the natural frequency of
your system.
Is the vibration being transmitted from
the rotary pump?
If so, fit flexible bellows or a vibration
isolator in the backing line.
Is the noise irregular and getting
progressively worse?
If so, a bearing is defective. Consult
BOC Edwards or your supplier.
Is the EXT Split Flow Pump making a
constant high-pitched noise?
If so, the rotor is out of balance.
Consult BOC Edwards or your
supplier.
None of the above. - Consult BOC Edwards or your
supplier.
Symptom Check Action
Table 7 - Fault finding (Continued)